That’s all someone needs

(something) is all (one) needs

Said ironically to indicate that something is not wanted or needed at all. Great, more interns to train—that's all I need! We're already struggling to keep up with everything our kids are doing, so a house full of relatives is all we need right now.
See also: all, needs

That’s all someone needs

sent. That is too much.; That is the last straw. Now the sewer’s backing up. That’s all I need.
See also: all, needs, someone